Subsequent Events	3 Months Ended
Mar. 31, 2017
Subsequent Events
Subsequent Events	12. Subsequent Events Exercise of Common Stock Warrants On April 12, 2017, the Company and Tech Opportunities LLC (“Tech Opps”) entered into an agreement, pursuant to which Tech Opps exercised in full its warrants to purchase an aggregate of 10,501,500 shares of Common Stock, at an exercise price of $1.50 per share, and the Company issued to Tech Opps warrants to acquire up to 5,250,750 shares of common stock at an exercise price of $2.69 per share. The aggregate cash exercise price paid to the Company pursuant to the exercise of the existing warrants was $15.8 million. During April 2017, the 4,000,000 warrants issued in January 2014 as part of an underwritten public offering with Heights Capital Management Inc., were exercised in full to purchase an aggregate of 4,000,000 shares of Common Stock, at an exercise price negotiated to be $0.65 per share. Conversion of Series D Preferred Stock On April 5, 2017, all of the outstanding shares of Series D Preferred Stock, were converted into an aggregate of 9,548,393 shares of Common Stock, at a conversion price of $1.55. The conversion was done at the election of the holder in accordance with the terms of the offering. No shares of Series D Preferred Stock remain outstanding. Amazon.com, Inc. Transaction Agreement On April 4, 2017, the Company and Amazon.com, Inc. (“Amazon”) entered into a Transaction Agreement (the “Transaction Agreement”), pursuant to which the Company agreed to issue to Amazon.com NV Investment Holdings LLC, a wholly owned subsidiary of Amazon, a warrant to acquire up to 55,286,696 shares of Common Stock, subject to certain vesting events (the “Warrant Shares”). The Company and Amazon entered into the Transaction Agreement in connection with existing commercial agreements between the Company and Amazon with respect to the deployment of the Company’s GenKey fuel cell technology at Amazon distribution centers. The existing commercial agreements contemplate future purchase orders for the Company’s fuel cell technology. The vesting of the warrant shares, is linked to payments made by Amazon or its affiliates (directly or indirectly through third parties) pursuant to the existing commercial agreements. At Market Issuance Sales Agreement On April 3, 2017, the Company entered into an At Market Issuance Sales Agreement (the “Sales Agreement”) with FBR Capital Markets & Co., as sales agent (“FBR”), pursuant to which the Company may offer and sell, from time to time through FBR, shares of common stock par value $0.01 per share having an aggregate offering price of up to $75.0 million. During April 2017, the Company issued 8,067,152 shares of Common Stock and raised net proceeds, after underwriting discounts and commissions and other fees and expenses, of $18.2 million, pursuant to the Sales Agreement.

12. Subsequent Events

Exercise of Common Stock Warrants

On April 12, 2017, the Company and Tech Opportunities LLC (“Tech Opps”) entered into an agreement, pursuant to which Tech Opps exercised in full its warrants to purchase an aggregate of 10,501,500 shares of Common Stock, at an exercise price of $1.50 per share, and the Company issued to Tech Opps warrants to acquire up to 5,250,750 shares of common stock at an exercise price of $2.69 per share. The aggregate cash exercise price paid to the Company pursuant to the exercise of the existing warrants was $15.8 million.

During April 2017, the 4,000,000 warrants issued in January 2014 as part of an underwritten public offering with Heights Capital Management Inc., were exercised in full to purchase an aggregate of 4,000,000 shares of Common Stock, at an exercise price negotiated to be $0.65 per share.

Conversion of Series D Preferred Stock

On April 5, 2017, all of the outstanding shares of Series D Preferred Stock, were converted into an aggregate of 9,548,393 shares of Common Stock, at a conversion price of $1.55. The conversion was done at the election of the holder in accordance with the terms of the offering. No shares of Series D Preferred Stock remain outstanding.

Amazon.com, Inc. Transaction Agreement

On April 4, 2017, the Company and Amazon.com, Inc. (“Amazon”) entered into a Transaction Agreement (the “Transaction Agreement”), pursuant to which the Company agreed to issue to Amazon.com NV Investment Holdings LLC, a wholly owned subsidiary of Amazon, a warrant to acquire up to 55,286,696 shares of Common Stock, subject to certain vesting events (the “Warrant Shares”). The Company and Amazon entered into the Transaction Agreement in connection with existing commercial agreements between the Company and Amazon with respect to the deployment of the Company’s GenKey fuel cell technology at Amazon distribution centers. The existing commercial agreements contemplate future purchase orders for the Company’s fuel cell technology. The vesting of the warrant shares, is linked to payments made by Amazon or its affiliates (directly or indirectly through third parties) pursuant to the existing commercial agreements.

At Market Issuance Sales Agreement

On April 3, 2017, the Company entered into an At Market Issuance Sales Agreement (the “Sales Agreement”) with FBR Capital Markets & Co., as sales agent (“FBR”), pursuant to which the Company may offer and sell, from time to time through FBR, shares of common stock par value $0.01 per share having an aggregate offering price of up to $75.0 million. During April 2017, the Company issued 8,067,152 shares of Common Stock and raised net proceeds, after underwriting discounts and commissions and other fees and expenses, of $18.2 million, pursuant to the Sales Agreement.